Carve is a dynamic EQ ducker. It takes the frequency signature of one audio signal and uses that as a profile to cut frequencies of a second audio signal. Maybe you have a guitar track and keyboard track that share the same frequency range. They might compete with each other and become muddy. Now, you can use Carve to take the frequency profile of some or all of the guitar track and remove those same frequencies from the keyboard track. No more muddiness!